The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 23, 2007
Filed:
Dec. 28, 2004
Applicants:
Hisashi Yano, Kyoto, JP;
Shinichiro Hayashi, Osaka, JP;
Inventors:
Hisashi Yano, Kyoto, JP;
Shinichiro Hayashi, Osaka, JP;
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 27/108 (2006.01); H01L 21/00 (2006.01); H01L 21/8242 (2006.01);
U.S. Cl.
CPC ...
Abstract
As a method for fabricating a semiconductor device, a lower electrode is first formed on a semiconductor substrate and then a first ferroelectric film is formed on the lower electrode by CVD using a first source gas. Thereafter, a second ferroelectric film is formed on the first ferroelectric film by CVD using a second source gas. Subsequently, an upper electrode is formed on the second ferroelectric film. In this method, the concentration of bismuth contained in the first source gas is different from the concentration of bismuth contained in the second source gas.